An imaging device includes an image input section which sequentially inputs image data with a predetermined time interval, a face detector to detect a face area of a subject from the image data, a rotational motion detector to detect a rotational motion between two frames of image data input with the predetermined time interval, and a controller to control the imaging device to execute a predetermined operation when the rotational motion is detected by the rotational motion detector. The rotational motion detector detects a candidate of rotational motion between the two frames of image data and calculate a coordinate of a rotation center and a rotational angle of the candidate, and determine whether or not the candidate is the rotational motion from a central coordinate of the detected face area, the coordinate of the rotation center and the rotational angle.